Foundation: Why quantum changes the security conversation

Why quantum changes the security conversation

The protection we rely on

Public-key cryptography helps establish secrets and authenticate systems. RSA and elliptic-curve techniques depend on mathematical problems that sufficiently capable fault-tolerant quantum computers could solve using Shor’s algorithm.

What changes—and what does not

This does not mean today's quantum computers routinely break real-world RSA or ECC. Symmetric cryptography such as AES has a different quantum threat profile and should not be confused with vulnerable public-key mechanisms.

Why action starts now

Harvest Now, Decrypt Later (HNDL) describes encrypted information being collected today for potential future decryption. The relevant decision is how long data must remain confidential, not merely the predicted date of a cryptographically relevant quantum computer.

The response

Post-quantum cryptography uses algorithms designed to resist known classical and quantum attacks on ordinary computers. Organisations should begin with visibility, risk assessment and a staged plan aligned to applicable ASD guidance.

Founder video: Why quantum changes the security conversation

This is a timed production outline, not a recorded video. The finished video will be no longer than five minutes.

1. 0:00–0:50 — Introduce a secure website connection and the role of public-key cryptography.
2. 0:50–1:50 — Explain RSA/ECC and Shor’s algorithm without advanced mathematics.
3. 1:50–2:55 — Illustrate HNDL with records that must remain confidential for many years.
4. 2:55–4:15 — Explain PQC and the first organisational questions.
5. 4:15–4:40 — Ask the learner to explain the risk in their own words.

Three things worth remembering

1. The protection we rely on: Public-key cryptography helps establish secrets and authenticate systems. RSA and elliptic-curve techniques depend on mathematical problems that
2. What changes—and what does not: This does not mean today's quantum computers routinely break real-world RSA or ECC. Symmetric cryptography such as AES has a different quantum th
3. Why action starts now: Harvest Now, Decrypt Later (HNDL) describes encrypted information being collected today for potential future decryption. The relevant decision is

Explain, don't guess

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Write a 120-word explanation to a nontechnical board member: what is HNDL, what is uncertain, and what should be assessed first?

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